I’m lost

In the beginning of January I had a period for two weeks then January 24th 2023 I had surgery my period was done that day I was just having the discharge and then after surgery I started bleeding heavy again for two weeks it stopped towards the end and beginning of February had sex or whatever Sunday February 19 I tested because I was having breast pain just to rule it out I tested and two digital test came back positive and then Monday I tested with the non digital test and the line was barely there I got a blood test yesterday and my count is 30.2 and I also had an ultrasound and there was nothing it was closed and that’s 3 surgeries in 3 months and they never tested me for pregnancy so I’m not sure I’m lost any advice or reassurance will help